JP2006267695A - Developing device, and process cartridge and image forming apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the stirring and mixing performance of toner to existing developer in a developer storing chamber with simple constitution. <P>SOLUTION: The developing device is equipped with: a developing unit 1 where a developer stirring and conveying member 3 is disposed in the developer storing chamber 2; and a toner replenishing unit 5 where a toner conveying member 7 is disposed in a toner replenishing chamber 6 and also where the toner replenishing chamber 6 is allowed to communicate with the developer storing chamber 2 of the developing unit 1 through a toner supply port 8. The toner supply port 8 of the toner replenishing unit 5 is opened so that its lower end may be positioned lower than the level position of the developer G stored in the developer storing chamber 2, and toner for replenishment T is supplied to the developer storing chamber 2 and also a part of the developer G in the developer storing chamber 2 is made to flow back in a direction (direction shown by an arrow β) opposite to a direction (direction shown by an arrow α) where the toner for replenishment is supplied. The process cartridge and the image forming apparatus including the developing device are also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a developing device used in an image forming apparatus such as an electrophotographic copying machine or a printer, and in particular, a developing unit that visualizes an electrostatic latent image on an image carrier and at least toner in the developing unit. The present invention relates to a developing device having a replenishable toner replenishing unit, a process cartridge using the developing device, and an image forming apparatus.

2. Description of the Related Art Conventionally, for example, in an electrophotographic image forming apparatus, an electrostatic latent image formed on an image carrier such as a photosensitive drum is developed with a developing device (visualized), and the toner image A system is generally employed in which the toner is transferred to a transfer medium such as a sheet or an intermediate transfer member by a transfer device, and the residual toner on the image carrier is recovered by a cleaning device.
As shown in FIG. 20 or FIG. 21, for example, the developing device 500 includes a developing unit 510 that contains a developer composed of toner and a carrier and is used for development. In order to extend, a developer replenishment unit 520 that replenishes the developer with respect to the developer consumption amount used in the development unit 510 is already provided (see Patent Documents 1 to 3).

Conventionally, of this type of developing device, in the developing device shown in Patent Document 1, the developing unit 510 has a developing housing 511 facing the image carrier 501 such as a photosensitive drum as shown in FIG. The developer housing 511 is provided with a developer containing chamber 512 in which a developer G made of, for example, toner and a carrier is housed, and a developing roll 513 is disposed at a portion facing the opening of the developing housing 511. Further, agitating and conveying augers 514 and 515 for agitating and conveying the developer G are disposed in the developer storage chamber 512.
On the other hand, the developer replenishment unit 520 has a replenishment container 521 in which a developer composed of, for example, toner and a carrier is accommodated, and the replenishment container 521 and the development housing 511 are communicated with each other through a communication duct 522 to provide a developer accommodation chamber. The developer in the replenishing container 521 can be replenished by dropping due to its own weight toward the upper side of the developer G accommodated in 512.
In FIG. 20, the developer supply unit 520 has a recovery container 530 capable of recovering the developer G deteriorated in the developer storage chamber 512, and the developer supply unit 520 is provided between the recovery container 530 and the development housing 511. Are communicated via a communication duct 531.

Further, in the developing devices shown in Patent Documents 2 and 3, the developing unit 510 is substantially the same as that described in Patent Document 1, but the developer replenishing unit 520 is as shown in FIG. A developer housing 541 having a partition wall 550 as a part of the developing housing 511 of the developing unit 510 is provided. In the supply housing 541, a developer supply chamber 542 in which a developer for supply is stored is provided. An agitator 543 for stirring and conveying is disposed in the chamber 542, and a developer replenishing mechanism and a developer collecting mechanism are provided on the developing unit 510 side of the developer replenishing chamber 542.
Here, in the developer supply mechanism, as shown in FIGS. 21A and 21B, a developer supply passage 545 is provided in the passage partition 544, and a supply auger 546 is disposed in the developer supply passage 545. And a supply port 547 is opened in the partition wall 550. However, the supply port 547 is above the center of the agitating / conveying auger 515, preferably the agitating / conveying auger, in order to smoothly supply the developer without receiving the pressure of the developer G from the developer containing chamber 512 side. It is provided above the surface position of the developer at the portion where 515 is disposed.
On the other hand, as shown in FIG. 21 (c), the developer recovery mechanism is provided with a developer recovery passage 555 in the passage partition 554, and a recovery auger 556 is provided in the developer recovery passage 555. A recovery port 557 is opened on the wall 550. However, the recovery port 557 is provided below the center of the agitating / conveying auger 515 in order to improve the recoverability of the developer from the developer storage chamber 512.

Japanese Patent Laying-Open No. 2001-305861 (Embodiment of the Invention, FIG. 4) JP-A-10-239970 (Embodiment of the Invention, FIG. 1) Japanese Patent Laid-Open No. 11-44997 (Embodiment of the Invention, FIG. 1) JP 10-142916 A (Embodiment of the Invention, FIG. 2)

However, in any of the developing devices described in Patent Documents 1 to 3 (a mode including a developer replenishment unit), replenishment developer is replenished from above the developer accommodated in the developer accommodation chamber of the development unit. The method to do is adopted.
At this time, since the replenishment developer has a high concentration and the filling ratio of the toner is higher than that of the carrier, the specific gravity of the replenishment developer is usually smaller than that of the developer in the developer storage chamber. In such a state, when the replenishment developer is replenished on the developer in the developer accommodating chamber, the replenishment developer floats on the existing developer, and the developer is removed by the agitating and transporting augers 514 and 515. There is a technical problem in that the replenishment developer is not sufficiently mixed even if it is stirred and conveyed, or it takes time to be mixed.
In particular, such a technical problem is that, in the embodiment where the replenishment developer is only toner, the specific gravity difference between the replenishment developer (toner) and the existing developer (toner and carrier) becomes large. The stir and mixing failure of the replenishment developer tends to appear more remarkably.

As a countermeasure for such a technical problem, in an aspect including a developing unit and a developer replenishing unit (toner replenishing unit), a sub chamber is provided in a portion adjacent to the developer accommodating chamber of the developing unit, and this A technique in which an agitating / conveying auger is provided in the sub chamber, the toner supplied from the toner supply port of the toner replenishing unit is dropped into the sub chamber, and after being agitated and mixed in advance by the agitating / conveying auger, the technology is supplied to the developer storage chamber. It has already been proposed (see, for example, Patent Document 4).
However, this type of developing device has a configuration in which a premixing mechanism (sub chamber + stirring conveyance auger) is added to the developing unit side, which not only complicates the device configuration but also increases the size of the device itself. In view of this, it is not preferable, and it takes time for pre-mixing, and accordingly, there is a possibility that the toner density followability is deteriorated (time delay).

  The present invention has been made in order to solve the above technical problems, and is based on the premise of a developing device including at least a toner replenishing unit capable of replenishing toner, and has an existing structure in a developer containing chamber with a simple configuration. The present invention provides a developing device, a process cartridge using the same, and an image forming apparatus that improve the stirring and mixing of toner with respect to the agent.

  That is, according to the present invention, as shown in FIGS. 1 (a) and 1 (b), a developer containing chamber 2 containing a developer G composed of toner and carrier is provided, and the developer agitating chamber 2 is provided with a developer stirring chamber. A developing unit 1 provided with a conveying member 3 and a developer carrying member 4 capable of carrying and conveying the developer G stirred and conveyed by the developer agitating and conveying member 3 and at least replenishment toner T The toner replenishing chamber 6 is accommodated. A toner conveying member 7 is disposed in the toner replenishing chamber 6, and the toner replenishing chamber 6 is connected to the developer accommodating chamber 2 of the developing unit 1 through the toner supply port 8. A toner replenishing unit 5 that communicates with the toner replenishing unit 5, and the toner replenishing port 5 of the toner replenishing unit 5 is opened so that its lower end is positioned below the surface position of the developer G accommodated in the developer accommodating chamber 2. And developing replenishment toner T A feature is that a part of the developer G in the developer storage chamber 2 is made to flow backward in a direction (arrow β direction) that is supplied to the storage chamber 2 and reverse to the supply direction of the replenishing toner (arrow α direction). .

In such technical means, the present case is premised on an aspect including the developing unit 1 and the toner replenishing unit 5.
The developing unit 1 only needs to include a developer storage chamber 2, a developer agitating / conveying member (auger) 3, and a developer carrier 4. Other functional members (members and layers for supplying the developer carrier 4) A forming member or the like may be provided as necessary.
Here, the developer G accommodated in the developer accommodating chamber 2 is a two-component developer composed of toner and carrier. Further, as a preferred embodiment of this type of developer accommodating chamber 2, for example, the developer accommodating chamber 2 is divided into two by a partition wall 2a extending along the axial direction of the developer carrier 4, and the length of the partition wall 2a is By opening communication ports 2b and 2c at both ends in the direction, a developer circulation path is formed in the developer storage chamber 2, and a pair of developer agitating and conveying members 3 (3a and 3b) are arranged in the developer circulation path. The aspect to set is mentioned.

The toner replenishing unit 5 contains the toner T for replenishment in principle, but in consideration of a so-called trickle system (a system in which the developer itself is replenished and the deteriorated developer is discarded and recovered), a part of the carrier is supplied with a carrier. Also included is a high-concentration replenishing toner containing.
Further, the toner replenishing unit 5 may be provided with a toner replenishing chamber 6, a toner conveying member 7, and a toner supply port 8. The toner replenishing unit 5 may be a single unit or may be divided into a plurality of parts.
Here, the toner replenishing chamber 6 may have a single chamber configuration. For example, the toner replenishing chamber 6 may have a plurality of chamber configurations, such as a configuration in which the toner is separated into a toner housing chamber 6a in which toner is stored and a dispensing chamber 6b in which replenishing toner can be replenished quantitatively. Is preferred. The toner conveying member 7 includes a wide range as long as it conveys at least the toner T toward the developing unit 1. The toner agitating / conveying member 7a that agitates and conveys the replenishing toner and the replenishing toner that has been agitated and conveyed are quantitatively replenished. For example, a dispense auger (dispensing member) 7b.

Further, it is sufficient that the toner supply port 8 is at least partially buried from the surface position of the developer G in the developer storage chamber 2, and the replenishment toner T is supplied to the developer accumulation portion of the developer storage chamber 2. By supplying from the side, the mixing property of the replenishment toner T to the existing developer G can be ensured.
In particular, the toner supply port 8 of the present case not only conveys the replenishment toner T but also functions as a part of the developer G to flow backward, and the developer that has flowed back to the toner in the toner supply chamber 6 facing the toner supply port 8. By preliminarily mixing G and supplying the toner T and the developer G, the mixing property of the toner T is kept good.

  Further, when the partial backflow phenomenon of the developer G is caught at another operation surface at the toner supply port 8, the two flows of the replenishment toner T and the developer G in the developer storage chamber 2 come into contact with each other at the interface. The phenomenon that the developer G is applied to the toner T at the interface is seen, and the force causing this phenomenon is assumed to be a shearing force. That is, the shearing force between the replenishment toner T and the developer G in the developer storage chamber 2 causes a change between the developer G and the replenishment toner T at the interface. It is assumed that this will lead to some backflow phenomenon.

  Furthermore, as a preferable developer partial backflow structure of the toner supply port 8, the replenishment toner T transport amount supplied to the developer storage chamber 2 through the toner supply port 8 is larger than the toner transport amount in the developer G that flows backward. As a result, the replenishability of the toner T is ensured. This is because if the toner conveyance amount in the developer G flowing backward is larger than the supplied toner conveyance amount, the toner replenishing chamber 6 is overfilled with toner at the portion facing the toner supply port 8, and the toner is not filled. This is because there is a concern that supply will be impaired.

Further, as a typical aspect of the partial reverse flow structure of the developer at the toner supply port 8, the distribution of the pressure at which the replenishment toner T in the toner replenishment unit 5 is pushed out from the toner supply port 8 is determined by the developer in the developer storage chamber 2. Examples include a mixture of a large portion and a small portion compared to the internal pressure due to G.
In other words, if the entire pressure distribution area due to the replenishment toner T is larger than the internal pressure due to the developer G, only the replenishment toner T is conveyed in one direction from the toner supply port 8. For this reason, it is assumed that in order for the developer G to flow backward, at least a portion facing the toner supply port 8 needs to have a location where the internal pressure by the developer G is greater than the pressure (internal pressure) by the replenishment toner T. Is done.

  Further, as a typical mode for realizing a partial developer reverse flow structure at the toner supply port 8, the toner transport direction in the portion of the toner supply chamber 6 facing the toner supply port 8, and the developer storage chamber 2. Of these, the developer conveying direction at the portion facing the toner supply port 8 is reversed. In this way, by reversing the toner conveyance direction and the developer conveyance direction at the portion sandwiching the toner supply port 8, a shearing force is easily generated at the interface between the replenishment toner T and the developer G. Accordingly, it is preferable in that it is easy to realize a partial backflow phenomenon of the developer G at the toner supply port 8.

  Here, the layout for reversing the toner transport direction and the developer transport direction across the toner supply port 8 may be appropriately selected. Typically, the toner supply port 6 faces the toner supply port 8. The toner conveyance direction at the part may be the one in the developer storage chamber 2 along the longitudinal direction along the axial direction of the developer carrier 4. In addition, the toner supply port 8 in the toner supply chamber 6 may be used. The toner conveyance direction at the part facing the surface is in the short side direction different from the axial direction of the developer carrier 4 in the developer storage chamber 2 or in the toner supply port 8 in the toner supply chamber 6. The toner conveying direction at the facing portion may be inclined with respect to the longitudinal direction along the axial direction of the developer carrier 4 in the developer storage chamber 2.

Further, as a preferable layout of the toner supply port 8, there is an embodiment in which the toner supply port 8 is opened at a position away from the end position of the developer storage chamber 2. Thus, by separating the toner supply port 8 from the end position of the developer accommodating chamber 2, it is possible to suppress a situation in which the developer reverse flow rate from the developer accommodating chamber 2 becomes excessive.
Furthermore, as a preferable aspect of the toner supply port 8, toner and developer are provided at the edge of the toner supply port 8 at the downstream side of the toner conveyance direction and the developer conveyance direction at the portion facing the toner supply port 8. The aspect which provides the hook-shaped return part which faces each conveyance direction of this is mentioned. By providing such a ridge-shaped returning portion, the operation of receiving and discharging the developer becomes smooth, and the premixing amount can be adjusted by appropriately setting the returning amount of the developer.

Further, as a preferable aspect of the toner transport member 7 in adopting the developer partial backflow structure, the toner replenishment unit 5 is provided with the toner transport member 7 facing the toner supply port 8, and the toner transport member 7. Among them, a part that faces the toner supply port 8 is used as a premixing unit 9 capable of premixing.
In particular, a typical embodiment of the toner replenishing unit 5 includes one provided with a dispensing mechanism. This dispensing mechanism is formed in a portion facing the toner supply port 8 in addition to at least the toner storage chamber 6a in which the supply toner T is stored as the toner supply chamber 6, and the supply toner T can be supplied quantitatively. A dispensing chamber 6b is provided, and a dispensing member 7b for quantitative replenishment is disposed as a toner conveying member 7 in the dispensing chamber 6b. In FIG. 1B, reference numeral 6c denotes a dispensing inlet opening that communicates the toner storage chamber 6a and the dispensing chamber 6b.
In those equipped with such a dispensing mechanism, the premixing section 9 may be provided in a part of the dispensing member 7b.

Here, as a typical aspect of the premixing portion 9 of the dispensing member 7b, the dispensing member 7b is constituted by an auger, and the portion of the dispensing member 7b facing the toner supply port 8 is used as a premixing portion 9 for damming. The aspect which provided the blade | wing member of this is mentioned. According to this aspect, the toner can be retained and the premixability can be improved.
Further, as another aspect, there is an aspect in which the dispensing member 7b is configured by an auger, and a blade member along the axial direction is provided as a premixing portion 9 in a portion of the dispensing member 7b facing the toner supply port 8. Can be mentioned. According to this aspect, it is possible to improve the premixability with the blade member.
Furthermore, as another aspect, the dispensing member 7b is configured by an auger, and the blade pitch of the portion of the dispensing member 7b facing the toner supply port 8 is set wider than that of the other portions, and the premixing unit 9 The embodiment which was made is mentioned. According to this aspect, the developer G circulating in the developer storage chamber 2 can be taken in more by widening the blade pitch.

The present invention is not limited to the above-described developing device, but can be applied to the following process cartridges and image forming apparatuses.
That is, as shown in FIG. 1A, the process cartridge according to the present invention is a process cartridge that is detachably attached to the main body of the image forming apparatus, and is opposed to the image carrier 11 and the image carrier 11. And the above-described developing device 12 capable of visualizing the electrostatic latent image on the image carrier 11.
Further, an image forming apparatus according to the present invention includes an image carrier 11 and the above-described developing device 12 that is disposed so as to face the image carrier 11 and can visualize an electrostatic latent image on the image carrier 11. The developing device 12 includes not only the process cartridge mode but also the non-process cartridge mode.

According to the developing device of the present invention, the toner supply port of the toner replenishment unit is arranged at a lower end thereof from the surface position of the developer accommodated in the developer accommodating chamber, in contrast to the aspect including the developing unit and the toner replenishment unit. Since the toner is opened so as to be positioned below, the replenishment toner can be supplied from the side to the developer accumulation portion of the developer storage chamber, and the agitation and mixing property of the replenishment toner to the developer can be improved. Can be secured.
In particular, according to the developing device according to the present invention, the toner supply port serves to transport the replenishing toner and to reverse a part of the developer, so that a separate premixing chamber is not provided in the developing unit. In the toner replenishing chamber facing the toner supply port, the replenished toner and the developer that has flowed backward can be premixed and then supplied as a single unit. The property can be kept good.
Further, according to the process cartridge or the image forming apparatus using such a developing device, it is possible to easily construct a process cartridge or an image forming apparatus in which the replenishment toner has good stirring and mixing properties.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
Embodiment 1
<Overall configuration of image forming apparatus>
FIG. 2 shows Embodiment 1 of an image forming apparatus to which the present invention is applied.
In the figure, the image forming apparatus is a so-called tandem type color image forming apparatus, and an image forming unit 22 (specifically, yellow, magenta, cyan, and black in this embodiment) is provided in the apparatus housing 21. 22a to 22d) are arranged in the vertical direction, and a paper feed cassette 23 for storing paper 24 for supply is arranged below the paper feed cassette 23, and a paper feed cassette is provided at a position corresponding to each image forming unit 22. 23, a sheet conveyance path 25 serving as a conveyance path for the sheet 24 from 23 is arranged in the vertical direction.

In the present embodiment, the image forming units 22 (22a to 22d) form toner images for yellow, magenta, cyan, and black in order from the upstream side of the sheet conveyance path 25, and various processes. A process cartridge 30 incorporating the unit and an exposure device 40 for irradiating the process cartridge 30 with scanning light for image formation are provided.
Here, the process cartridge 30 includes, for example, a photosensitive drum 31, a charging roll 32 that precharges the photosensitive drum 31, and an electrostatic device that is exposed and formed by the exposure device 40 on the charged photosensitive drum 31. A developing device 33 that develops the latent image with corresponding color toner (for example, negative polarity in the present embodiment), a cleaning device 34 that removes waste toner on the photosensitive drum 31, and a surface of the charged photosensitive drum 31 And an erase lamp 35 for neutralizing the battery.
On the other hand, the exposure apparatus 40 stores a semiconductor laser (not shown), a polygon mirror 42, an imaging lens 43 and a mirror 44 in the case 41, and deflects and scans the light from the semiconductor laser with the polygon mirror 42. The optical image is guided to the exposure point on the photosensitive drum 31 through the mirror 44.

Further, in the present embodiment, a conveyance belt 53 that circulates along the sheet conveyance path 25 is disposed at a position corresponding to each photosensitive drum 31 of each image forming unit 22.
The conveyor belt 53 is made of a belt material (rubber or resin) that can electrostatically attract the paper 24, and is stretched between a pair of tension rolls 51 and 52. The rack roll 52 is a driving roll, and the lower tension roll 51 is a driven roll.

  Furthermore, a paper suction roll 54 is disposed at the entrance portion of the transport belt 53 (the portion facing the stretching roll 51). By applying a high voltage suction voltage to the paper suction roll 54, the transport belt 53 is provided. The sheet 24 is attracted to the sheet. Further, a transfer roll 50 is disposed on the back side of the conveyance belt 53 corresponding to the photosensitive drum 31 of each image forming unit 22, and the sheet 24 on the photosensitive drum 31 and the conveyance belt 53 is transferred by the transfer roll 50. And more closely. A predetermined transfer bias by a transfer bias power source is appropriately applied between the transfer roll 50 and the photosensitive drum 31.

In the present embodiment, a pickup roll 61 is provided in the vicinity of the paper feed cassette 23 to feed the paper 24 at a predetermined timing. The pickup roll 61 is moved to the transfer position via the transport roll 62 and the registration roll 63. It comes to send.
Further, a fixing device 64 is provided in the paper conveyance path 25 located on the downstream side of the most downstream image forming unit 22d, and a discharge roll 66 for discharging paper is provided on the downstream side of the fixing device 64. The discharged paper is stored in a storage tray 67 formed on the upper portion of the apparatus housing 21.
In FIG. 2, reference numeral 80 denotes a high-voltage power supply that supplies a high voltage to the high-voltage device, and reference numeral 81 denotes a low-voltage power supply that supplies a low voltage to the low-voltage device.

The image forming process of such an image forming apparatus is as follows.
As shown in FIG. 2, in each image forming unit 22 (22 a to 22 d), after the photosensitive drum 31 is charged by the charging roll 32 and a latent image is formed on the photosensitive drum 31 by the exposure device 40. A visible image (toner image) is formed by the developing device 33.
On the other hand, the paper 24 from the paper feed cassette 23 is fed out at a predetermined timing by the pickup roll 61, sent to the suction position of the transfer belt 53 via the conveyance roll 62 and the registration roll 63, and is conveyed to the conveyance belt 53. It is sent to the transfer position in the adsorbed state.
Then, the toner images on the photosensitive drum 31 in each image forming unit 22 are respectively transferred to the paper 24 by the transfer roll 50, and each color component unfixed toner image on the paper 24 is fixed by the fixing device 64 and then fixed. The used paper 24 is discharged to the storage tray 67.

<Outline of process cartridge>
FIG. 3 shows details of the process cartridge 30 used in the present embodiment.
In the figure, a process cartridge 30 includes a photosensitive drum 31, a charging roll 32, a part of a developing device 33, a cleaning device 34, and an erase lamp 35 as a device for discharging the photosensitive drum 31 before the cleaning process. A photosensitive cartridge 30a included, and a developing cartridge 30b provided below the photosensitive cartridge 30a so as to be swingable and positioned with respect to the photosensitive cartridge 30a and including a main part of the developing device 33. And.

In particular, in the present embodiment, the developing device 33 faces the photosensitive drum 31 and visualizes the electrostatic latent image on the photosensitive drum 31 with a developer G composed of toner and carrier. And toner replenishing units 110 and 120 for replenishing toner T to the developing unit 100 (in this embodiment, a separate type from the main toner replenishing unit 110 and the sub toner replenishing unit 120 is employed).
The photosensitive cartridge 30a has a configuration in which a cleaning unit 200 in which the cleaning device 34 is unitized and a sub-toner replenishment unit 120 are integrated in the horizontal direction, and the development cartridge 30b has a development unit 100 and a main toner replenishment unit. 110 is integrated in the horizontal direction.

  Further, in the present embodiment, the developing cartridge 30b is provided at the developing unit 100 portion so as to be swingable by the pivot shaft 30c with respect to the photosensitive cartridge 30a positioned and fixed to the apparatus housing 21, and the photosensitive cartridge 30a. A scanning passage 135 through which scanning light from the exposure device 40 can pass is secured between the developing cartridge 30b and an elastic member on both sides of each part cartridge 30a, 30b near the entrance of the scanning passage 135. A spacer 130 is interposed to pressurize the developing cartridge 30b against the photosensitive cartridge 30a. Of course, a biasing element such as a biasing spring may be used instead of or in addition to the spacer 130.

In the present embodiment, the sub-toner replenishment unit 120 of the photoconductor cartridge 30a extends in a direction orthogonal to the axial direction of the photoconductor drum 31, as shown in FIGS. 3 and 4A and 4B, for example. A pair of support protrusions 141 are provided.
Then, when the process cartridge 30 is mounted in a cartridge receiving portion (not shown) of the apparatus housing 21, both ends of the support shaft that rotatably supports the photosensitive drum 31 are not shown in the drawing provided in the cartridge receiving portion. A drive transmission member (for example, a drive transmission gear) disposed at one end of the photosensitive drum 31 that is fixed at a predetermined position by the fixed receiving member and is rotatably disposed on the support shaft is a cartridge receiving portion. It is connected and engaged with a drive system (not shown) provided in The pair of support protrusions 141 are engaged with engaged portions (such as recesses and holes) of the cartridge receiving portion so that the photosensitive cartridge 30 a is positioned and fixed to the apparatus housing 21. Here, the cartridge receiving portion of the apparatus housing 21 may be any as long as it can accommodate and hold the process cartridge 30, and may be configured using the housing frame itself, or may be configured by providing another member on the housing frame. May be.
In particular, in the present embodiment, the support protrusion 141 is provided on the outer wall of the unit away from the photosensitive drum 31 and suppresses the rotation of the process cartridge 30 due to the driving force that drives the photosensitive drum 31. It also has a function.
In FIG. 4, reference numeral 142 denotes a gripping arm used when the process cartridge 30 is attached and detached.

<Developing device>
The units 100, 110, and 120 constituting the developing device 33 used in this embodiment will be described.
-Development unit-
In the present embodiment, the developing unit 100 employs a so-called two-component developing system as shown in FIGS. 3, 5, and 6, and the photosensitive drum 31 is disposed below the photosensitive drum 31. The developing housing 101 is open to the side, and the developing housing 101 is configured as a developer containing chamber 102 in which a developer G composed of toner and carrier can be stored, and development is performed at a portion facing the opening of the developing housing 101. A developing roll 103 for supporting the agent is disposed. The developing unit 100 bisects the developer accommodating chamber 102 with a partition wall 106 extending along the axial direction of the developing roll 103, and opens communication ports 107 and 108 at both longitudinal ends of the partition wall 106. As a result, a developer circulation path is formed in the developer storage chamber 102, and a pair of agitation transport augers 104 and 105 are disposed along the axial direction of the developing roll 103 in this developer circulation path. The developer G inside is conveyed while stirring.
Here, the agitating / conveying auger 104 is an admix auger whose main purpose is to agitate and mix the toner T replenished exclusively to the existing developer G. On the other hand, the agitating / conveying auger 105 is added to the agitating and mixing function of the toner. This is a supply auger responsible for the developer supply function to the developing roll 103.
In this embodiment, the agitating / conveying auger 105 near the developing roll 103 also serves as a developer supplying function to the developing roll 103. However, a developer supplying member (roll, paddle, etc.) is provided separately from the agitating / conveying auger 105. Of course, it may be added. Further, a trimming member for regulating the developer layer thickness, a collecting member for collecting unused developer, and the like are provided around the developing roll 103 as necessary.

-Main toner supply unit-
Further, as shown in FIGS. 3, 5 and 6, the main toner replenishment unit 110 has a main replenishment housing 111 which also serves as a part of the rear partition wall of the developing housing 101 of the developing unit 100. 111 is configured as a toner replenishing chamber in which replenishing toner T is accommodated so as to be replenished.
In particular, in the present embodiment, the toner supply chamber communicates with the toner storage chamber 112 in which the supply toner T is stored, and the toner storage chamber 112, and quantitatively supplies the toner T to the developing unit 100. It is divided into a dispensing chamber 113. Here, the dispensing chamber 113 is provided with a thick portion 101b near the lower portion of the rear partition 101a of the developing housing 101, and a long passage having a substantially circular cross section extending along the axial direction of the developing roll 103 in the thick portion 101b. It is configured as a (tunnel-shaped passage).
A dispensing inlet opening 114 is formed in a portion facing the toner storage chamber 112 on the inner side in the longitudinal direction of the thick portion 101b, and a portion facing the developer storage chamber 102 in the thick portion 101b. A toner supply port 115 is opened on the opposite side of the dispensing inlet opening 114 in the longitudinal direction.

Further, an agitator 116 for agitating and conveying the replenishing toner T in the toner storage chamber 112, and an agitator for agitating and conveying the toner T agitated and conveyed by the agitator 116 toward the dispensing inlet opening 114 of the dispensing chamber 113. 117 is disposed.
Here, as shown in FIG. 5, the agitator 116 has an agitate film 402 made of a PET film or the like at the tip of a crank-shaped rotating rod 401, and the toner is transported along the wall of the toner supply chamber by the agitate film 402. To do. An appropriate number of stirring rods 403 extending in the radial direction of the rotating rod 401 are provided on the opposite side of the rotating rod 401 from the agitator film 402 so as to stir the toner in the toner supply chamber. The agitator 117 may be configured in substantially the same manner as the agitator 116, but it is preferable to adjust the toner conveyance direction toward the dispense inlet opening 114 by, for example, appropriately cutting the agitate film. However, as agitator 116, 117, it is needless to say that a stirring and conveying coil spring or the like may be used.
In FIG. 6, the forms of the agitators 116 and 117 are schematically shown.
On the other hand, a dispense auger 118 is disposed in the dispense chamber 113 along the longitudinal direction. In particular, in the present embodiment, the dispense auger 118 is provided with a spiral blade having a diameter substantially equal to or less than that of the agitating / conveying augers 104 and 105 in the developing unit 100, and the pitch of the dispense auger 118 is further reduced. The pitch is set to be equal to or less than the pitch of the agitation transport augers 104 and 405.

In the present embodiment, as shown in FIGS. 7A and 7B, the lower end of the toner supply port 115 is located below the surface position of the developer G stored in the developer storage chamber 102. So that it is open. That is, the toner supply port 115 only needs to be buried at least from the surface position of the developer G in the developer storage chamber 102, and the replenishment toner T can be supplied from the side to the developer accumulation portion of the developer storage chamber 102. The mixing and mixing properties of the toner T for the developer to the developer are ensured.
In particular, in the present embodiment, the toner supply port 115 supplies the replenishment toner T to the developer storage chamber 102 and also supplies the replenishment toner (in the direction of arrow α), as shown in FIGS. ) In a direction (arrow β direction) opposite to that of the developer G in the developer storage chamber 102.

  Specifically, the toner transport direction at the portion facing the toner supply port 115 in the dispense chamber 113 and the developer transport direction at the portion facing the toner supply port 115 in the developer storage chamber 102 are reversed. In addition, a shearing force is generated at the interface between the replenishing toner T and the developer G, and a circulating flow as indicated by α and β is generated with respect to the toner T and the developer G. The dispensing auger 118 has a damming auger blade 118b at a portion facing the toner supply port 115 in addition to a normal agitating and conveying auger blade 118a. Since the toner T is temporarily retained in this area, the toner retention area functions as a premix area PM for premixing the toner T and the developer G.

That is, a part of the developer G transported by the stirring transport auger (admix auger) 104 enters the tunnel-like dispense chamber 113 in which the dispense auger 118 is disposed from the toner supply port 115, The rotation of the auger blade 118a conveys the toner together with the toner in the direction opposite to the developer moving direction, and reaches the toner retention area (preliminary mixing area PM).
At this time, the developer that has flowed around the replenishing toner T clumps as if it is yellowish powdery yellow powder, passes through the toner retention area, and again from the toner supply port 115 through the toner supply port 115 by the auger blade 118b for preventing clogging. It is pushed out to 102.
At the time of the extrusion, the developer G is coated like yellow powder around the replenishment toner T as described above, so that it is heavier than the case of the toner alone. Accordingly, it becomes difficult for the replenishing toner T replenished from the toner supply port 115 to float on the surface of the developer G conveyed by the admix auger 104. Stir and mixability is improved.

Further, in such a mode in which a partial backflow phenomenon of the developer occurs, the pressure distribution in which the replenishment toner T in the dispense chamber 113 is pushed out from the toner supply port 115 is caused by the developer G in the developer storage chamber 102. A portion that is larger and smaller than the internal pressure is mixed, and the replenishment toner T is supplied to the developer storage chamber 102 from a portion where the pressure of the replenishment toner T is greater than the internal pressure of the developer G in the developer storage chamber 102. On the contrary, it is estimated that the developer G enters the dispensing chamber 113 from a small portion.
Accordingly, the transport amount, transport speed, auger diameter, auger pitch, and the like of the dispense auger 118 and the admix auger 104 are appropriately selected so that a partial backflow phenomenon of the developer G is possible.

Further, in the present embodiment, the toner supply port 115 is opened at a position away from the end position of the developer accommodating chamber 102, so that the developer reverse flow rate from the developer accommodating chamber 102 becomes excessive. Can be effectively suppressed.
Furthermore, if the lower end of the toner supply port 115 is set below the rotation center of the admix auger 104, the toner T is replenished from below the rotation center of the admix auger 104. It is caught in the mix auger 104 and quickly stirred and mixed with the developer.
Further, since the center of the dispense auger 118 is set to be substantially the same as or below the rotation center of the admix auger 104, toner is supplied from below the rotation center of the admix auger 104. Accordingly, the replenished toner is taken up in the admix auger 104 and quickly stirred and mixed.

Furthermore, the dispense inlet opening 114 may be appropriately opened, but from the viewpoint of sufficiently increasing the toner internal pressure in the dispense chamber 113, the dispense inlet opening 114 should be larger than the pitch of the dispense auger 118. preferable. Further, it is preferable that the transport length of the replenishment toner T in the dispense chamber 113 is sufficiently longer than the dispense inlet opening 114.
Further, regarding the capacity of the toner storage chamber 112, if the capacity of the toner storage chamber 112 is made larger than the capacity of the dispense chamber 113 or the total capacity of the dispense chamber 113 and the developer storage chamber 102, the toner supply port 115 can be used. The toner can be continuously and stably supplied.
Furthermore, in the present embodiment, the rotational centers of the agitators 116 and 117 are arranged so as to be positioned above the dispense auger 118 and the stirring and conveying augers 104 and 105.
Therefore, there is no need to lift the toner T from the toner storage chamber 112 to the dispensing chamber 113 and the developer storage chamber 102, so that the toner internal pressure in the dispense chamber 113 can be effectively increased, and the toner internal pressure in the dispense chamber 113 can be increased. The toner can be smoothly supplied to the developer storage chamber 102 without impairing the toner.

-Sub-toner supply unit-
Further, in the present embodiment, the sub-toner replenishment unit 120 has a sub-replenishment housing 121 adjacent to the back side of the cleaning unit 200, as shown in FIG. It is configured as a toner replenishing chamber 122 that is accommodated so as to be replenished.
In the toner supply chamber 122, a pair of agitators 123 and 124 for stirring and transporting the supply toner T are disposed.
Here, as a communication structure between the sub-toner supply unit 120 and the main toner supply unit 110, as shown in FIGS. 3 and 8, a spacer 130 made of an elastic member is formed with a communication path (toner supply path) 131. Used. In the present embodiment, the spacers 130 are provided at two positions on both sides between the units 110 and 120, and the toner supply paths 131 are formed respectively. For example, the toner supply paths 131 are provided only in one of the spacers 130. Alternatively, the spacer 130 may be provided at one location on one side, and the toner supply path 131 may be formed in the spacer 130.
In the present embodiment, as shown in phantom lines in FIG. 8, the sub toner replenishment unit 120 preferably closes the connecting portion with the toner supply path 131 with a seal member 125 that can be opened when in use. . In this case, when the process cartridge 30 is not used (for example, during transportation), the toner in the sub toner replenishment unit 120 enters the toner supply path 131 and there is no fear of clogging, and the toner in the sub toner replenishment unit 120 is the main toner. It is possible to effectively avoid a situation in which the toner filling density in the main toner replenishing unit 110 is unnecessarily increased because the toner is charged in the replenishment unit 110 side.

In this embodiment, when a predetermined amount of toner T is supplied from the main toner supply unit 110 to the developing unit 100, the toner T in the sub toner supply unit 120 is supplied to the main toner supply unit 110 at the same time. It has become so. For this reason, the main toner replenishment unit 110 is filled with the substantially constant toner T until the sub toner replenishment unit 120 becomes empty, and the change in the weight of the developing cartridge 30b is suppressed to a small extent.
At this time, since the photosensitive cartridge 30a is positioned and fixed with respect to the cartridge receiving portion of the apparatus housing 21, the change in the toner storage amount of the sub toner replenishment unit 120 does not affect the change in the weight of the developing cartridge 30b.
Therefore, fluctuations in the pressing and urging force of the developing cartridge 30b with respect to the photosensitive cartridge 30a are suppressed until the sub-toner replenishing unit 120 is empty, and image disturbance can be effectively prevented correspondingly.

  Further, since the photosensitive member cartridge 30a is positioned and fixed to the apparatus housing 21, at least the lower surface position of the photosensitive member cartridge 30a forming the scanning passage 135 does not change, and accordingly, the photosensitive member cartridge 30a. Even if the position of the developing cartridge 30b that is pivotally supported is changed, there is little possibility that the scanning passage 135 is blocked.

<Cleaning device>
In the present embodiment, the cleaning device 34 is incorporated as a cleaning unit 200 in the photosensitive member cartridge 30a as shown in FIG.
The cleaning unit 200 includes a cleaning housing 201 that opens to face the photosensitive drum 31. The cleaning housing 201 is configured as a waste toner storage chamber 203 that can store waste toner, and an upper wall of the cleaning housing 201. 201a is extended in a bowl shape toward the photosensitive drum 31 side.
A cleaning blade 210 is disposed on the lower opening edge 201b of the cleaning housing 201. The cleaning blade 210 is a side wall (see FIG. 5) that hangs down from both the opening lower edge 201b and the upper wall 201a of the cleaning housing 201. (Not shown), a substantially L-shaped blade holder 212 is attached, and a blade body 211 made of an elastic material such as urethane rubber is attached to the outside of the distal end portion of the blade holder 212, and the distal end of the blade body 211 is attached to the photosensitive drum 31. It is elastically contacted so as to face the rotation direction (counterclockwise direction in FIG. 9).
On the other hand, a film seal 215 such as PET or polyurethane is provided at the upper edge of the opening of the cleaning housing 201 (in the present embodiment, in the vicinity of the front end of the upper wall 201a), and the front end of the film seal 215 is the rotation of the photosensitive drum 31. Elastic contact is made along the direction to prevent the waste toner collected by the cleaning blade 210 from scattering.

In the present embodiment, the portion other than the attachment portion of the cleaning blade 210 to the cleaning housing 201 is disposed substantially parallel to the bowl-shaped portion of the upper wall 201a of the cleaning housing 201, and the waste toner scraped off by the cleaning blade 210 is used. Is configured as a waste toner reservoir portion 213 (corresponding to the inner surface of the blade holder 212 in this example). In particular, in this example, the waste toner reservoir 213 has a downward slope toward the waste toner storage chamber 203, so that the transportability of the waste toner Td can be improved.
In the present embodiment, the waste toner reservoir 213 is configured by only the cleaning blade 210, but may be configured by using not only the cleaning blade 210 but also a part of the cleaning housing 201.
Further, since a space that becomes a recess with respect to the photosensitive drum 31 is secured between the cleaning housing 201 and the cleaning blade 210, the charging roll 32 is disposed using the recess.
A holding block 202 for the erase lamp 35 is provided at the tip of the upper wall 201a of the cleaning housing 201.

Further, in the present embodiment, a waste toner transport member 220 that transports the waste toner Td scraped by the cleaning blade 210 to the waste toner storage chamber 203 side is provided in the cleaning housing 201.
The waste toner transport member 220 has a transport plate 221 as a member element straddling between the waste toner storage chamber 203 and the waste toner reservoir 213, and is disposed at the end of the transport plate 221 on the side of the waste toner storage chamber 203. A drive input unit 222 capable of inputting an external driving force is provided, and a protrusion 223 capable of contacting the waste toner reservoir 213 is provided at the end of the transport plate 221 on the photosensitive drum 31 side.
Here, the transport plate 221 may remain plate-shaped, but from the viewpoint of reducing the weight and effectively avoiding the accumulation of the waste toner Td on the upper surface portion, the protruding portion 223 of the transport plate 221 and the drive input. It is preferable to form the opening 224 in a portion other than the portion 222. In addition, the projecting portion 223 is not necessarily formed at the end portion of the transport plate 221, and may be a portion away from the end portion, and the number of the projecting portions 223 may be at least one. There may be more than one. Further, the method for forming the protruding portion 223 is appropriately selected, for example, by bending the tip portion of the transport plate 221 or by forming the protruding portion 223 integrally or separately on a part of the transport plate 221. It does not matter.
Of course, the member element of the waste toner conveying member 220 is not necessarily the conveying plate 221, and it is of course possible to use a frame frame structure, for example.

In this embodiment, for example, as shown in FIG. 9, a driving force in the form of a rotation locus is input to the drive input unit 222 of the waste toner conveying member 220. The force can be easily obtained, for example, by rotating a crankshaft 231 that is a kind of the rotation drive mechanism 230 around the rotation center.
Further, in the present embodiment, the waste toner conveying member 220 is provided with a posture regulating mechanism 240 for regulating the movement posture of the waste toner conveying member 220.
In the present embodiment, the attitude regulating mechanism 240 is configured by a biasing spring 241 that has one end engaged with the protruding portion 223 side of the waste toner conveying member 220 and the other end engaged with a part of the cleaning housing 201. The waste toner conveying member 220 is biased in a direction away from the drive input unit 222.

In particular, in the present embodiment, the urging spring 241 is disposed in an oblique direction with respect to the advancing / retreating direction of the waste toner conveying member 220.
Here, as a mounting structure of the urging spring 241, in FIGS. 9 and 10, locking hooks 242 and 243 are provided at both ends of the urging spring 241, and one of the locking protrusions 204 on the cleaning housing 201 side is locked. The hook 242 is engaged, and the other hook 243 is engaged with the engagement piece 225 provided at the end of the waste toner conveying member 220 on the protruding portion 223 side.
In this embodiment, the engagement protrusion 204 is provided in the cleaning housing 201 as a mounting structure of the urging spring 241. However, the present invention is not limited to this, and for example, communicates with the cleaning housing 201 to the outside. In a mode in which the locking hole is opened, there is a risk of waste toner leakage. In such a case, the locking hole may be sealed with a seal member. As this sealing member, it is preferable to also use a label or the like attached to the CRU.

As described above, when the urging spring 241 is attached to the waste toner conveying member 220, as shown in FIGS. 9 and 10, when a rotational locus-like driving force is input to the drive input portion 222 of the waste toner conveying member 220, as shown in FIGS. Following this, the protrusion 223 of the waste toner conveying member 220 moves forward and backward along the waste toner reservoir 213.
At this time, the biasing spring 241 regulates the posture change range of the waste toner transport member 220 with respect to the change in the position of the drive input unit 222 of the waste toner transport member 220. In this example, when the waste toner transport member 220 moves backward, the protrusion 223 moves in contact with the waste toner along the waste toner reservoir 213, and when the advance toner moves, the protrusion 223 moves to the waste toner reservoir 213. It moves non-contactingly. Specific behavior will be described later.
In particular, in the present embodiment, the urging spring 241 is disposed obliquely with respect to the advancing / retreating direction of the waste toner conveying member 220, so that it is possible to save the space for disposing the waste toner. The amount of expansion / contraction of the urging spring 241 can be set small with respect to the amount of movement of the conveying member 220, which is preferable in that the fluctuation of the driving force applied to the waste toner conveying member can be reduced accordingly.

Next, the operation of the cleaning device 34 used in the present embodiment will be described.
As shown in FIGS. 9 and 11A, when the residual toner on the photosensitive drum 31 is scraped off by the cleaning blade 210, the scraped waste toner Td is accumulated on the cleaning blade 210 and in the vicinity thereof. However, after being pushed out one after another by the scraped toner, the waste toner Td accumulates on the waste toner reservoir 213 (in this example, the inner surface of the blade holder 211 corresponds).
In such a state, if the drive input unit 222 of the waste toner transport member 220 is now in the position of FIG. 11A, the waste toner transport member 220 is disposed at the most advanced position.
At this time, the urging spring 241 urges the waste toner conveying member 220 in a direction away from the drive input unit 222, but the position of the driving input unit 222 of the waste toner conveying member 220 and the cleaning housing of the urging spring 241. By adjusting the relationship with the locking point position on the 201 side, a part of the urging force component of the urging spring 241 causes the protrusion 223 of the waste toner conveying member 220 to contact the waste toner on the waste toner reservoir 213. If acting in the direction, the protruding portion 223 of the waste toner conveying member 220 contacts the waste toner on the waste toner reservoir 213.

When the position of the drive input portion 222 is rotated downward by the rotation drive mechanism 230 from this state, as shown in FIG. 11B, the waste toner conveying member 220 moves backward while being gradually inclined. The protruding portion 223 of the toner conveying member 220 conveys the waste toner on the waste toner reservoir 213 toward the waste toner storage chamber 203 side.
When the drive input unit 222 of the waste toner conveying member 220 reaches the lowest point, the posture of the waste toner conveying member 220 becomes the steepest inclination, but the protruding portion 223 of the waste toner conveying member 220 and the waste toner reservoir portion. From the standpoint of maintaining the contact state with 213, it is efficient to keep the portion other than the protruding portion 223 of the waste toner conveying member 220 out of contact with the waste toner reservoir 213.
Thereafter, when the drive input unit 222 of the waste toner conveying member 220 is rotated to the position shown in FIG. 11C, the waste toner conveying member 220 is further moved backward while gradually relaxing the inclined posture. At this time, the urging spring 241 still acts to press the waste toner conveying member 220 toward the waste toner reservoir 213, so that the protruding portion 223 of the waste toner conveyance member 220 is disposed along the waste toner reservoir 213 with the waste toner Td. To move the waste toner Td to the waste toner storage chamber 203 side.
In this embodiment, as shown in FIGS. 11C and 12A, even if the waste toner conveying member 220 reaches the last retracted position, the protruding portion 223 of the waste toner conveying member 220 is discarded. Although the waste toner does not move to the end of the toner reservoir 213 closer to the waste toner storage chamber 203, the waste toner transported to the vicinity of the end of the waste toner storage 213 closer to the waste toner storage chamber 203 is waste toner transported later. Are sequentially stored in the waste toner storage chamber 203.

In this embodiment, as shown in FIG. 12A, when the waste toner conveying member 220 reaches the last retracted position, the waste toner conveying member 220 is pulled by the urging force of the urging spring 241 and the waste toner is conveyed. The protruding portion 223 of the conveying member 220 is separated from the waste toner on the waste toner reservoir 213 and reaches a state just before being arranged in a non-contact manner.
That is, since the waste toner conveying member 220 is urged in a predetermined direction by the urging spring 241, the relationship between the position of the drive input portion 222 of the waste toner conveying member 220 and the locking point position of the urging spring 241 on the cleaning housing 201 side. Based on this, the arrangement posture of the waste toner conveying member 220 is determined. At this time, when the waste toner conveying member 220 shifts to the advancing movement, the layout should be such that the protruding portion 223 of the waste toner conveying member 220 and the waste toner on the waste toner reservoir 213 are arranged in a non-contact manner. Good.

Thereafter, as shown in FIG. 12B, when the drive input unit 222 of the waste toner transport member 220 rotates upward, the waste toner transport member 220 advances while changing the tilting posture so that the drive input unit 222 side rises. Moving.
At this time, the waste toner conveying member 220 is urged by the urging spring 241. When the position of the drive input portion 222 of the waste toner conveying member 220 is raised, the arrangement position of the waste toner conveying member 220 is further raised. Therefore, the protruding portion 223 of the waste toner conveying member 220 and the waste toner on the waste toner reservoir 213 remain arranged in a non-contact manner.
Thereafter, as shown in FIG. 12C, when the drive input unit 222 of the waste toner transport member 220 rotates in a direction to be lowered from the top dead center position, the waste toner transport member 220 moves forward while changing the tilt posture again. And gradually approaches the waste toner reservoir 213 side. When the waste toner conveying member 220 reaches the most advanced position, the protruding portion 223 of the waste toner conveying member 220 is again placed in contact with the waste toner on the waste toner reservoir 213.
As described above, when the waste toner transport member 220 moves forward, the protrusion 223 of the waste toner transport member 220 moves in a non-contact manner with respect to the waste toner on the waste toner reservoir 213. Thus, the situation where the waste toner on the waste toner reservoir 213 is pushed back is effectively avoided, and the transportability of the waste toner is kept good.
Thereafter, the behaviors of FIGS. 11A to 11C and FIGS. 12A to 12C are repeated.
In the present embodiment, the waste toner conveying member 220 is in a state of moving in contact with the waste toner reservoir portion 213 during the backward movement. However, the present invention is not limited to this. For example, the waste toner conveying member 220 includes: Of course, in the backward movement region, the waste toner reservoir 213 may be moved in a non-contact manner first, and may be moved in the middle.

In particular, in the present embodiment, the waste toner conveying member 220 maintains a substantially horizontal uppermost position when the drive input unit 222 is at the top dead center position, and moves along a trajectory that does not protrude upward from the uppermost position. In addition, since the advancing movement is performed while maintaining a substantially horizontal posture, the upper space of the waste toner storage chamber and the upper space of the waste toner reservoir 213 can be set narrow, and the cleaning device 34 is made thin accordingly. It is possible to
In this embodiment, since the waste toner conveying member 220 has the opening 224, there is no concern that the waste toner is accumulated on the waste toner conveying member 220 when the waste toner conveying member 220 conveys the waste toner. In addition, there is no concern that waste toner is scattered by wind pressure due to air resistance.
Further, in the present embodiment, the waste toner conveying member 220 moves in contact with the waste toner reservoir 213 during the backward movement, but is not limited to this, and is not in contact with the waste toner reservoir 213. However, it may be moved in contact with the waste toner on the waste toner reservoir 213. In this case, since the waste toner conveying member 220 does not come into direct contact with the waste toner reservoir 213 during the backward movement, vibration is unnecessarily transmitted to the photosensitive drum 31 as the waste toner conveying member 220 moves. This is preferable in that there is less concern about the occurrence of the problem.

<Drive system of developing device and cleaning device>
In the present embodiment, the driving system 300 of the developing device 33 and the cleaning device 34 may be appropriately selected, but the following are used, for example.
That is, the drive system 300 used in the present embodiment is configured such that each driven element of the toner supply units 110 and 120 in the developing device 33 and each drive of the cleaning unit 200 as the cleaning device 34 are shown in FIG. A transport drive system 301 that drives the elements with the same drive source, and a development drive system 302 that drives each drive element of the development unit 100 in the developing device 33 using a drive source different from the transport drive system 301. It has.

Here, the transport drive system 301 has a drive input gear 311 that is drivingly connected to a drive source (not shown). The drive input gear 311 is engaged with a first-stage drive transmission gear 312, A coaxial transmission gear 313 is provided coaxially, and the coaxial transmission gear 313 is engaged with drive transmission gears 315 and 316 connected to the agitators 116 and 117 of the main toner replenishing unit 110 via an idler gear 314, and further, one drive transmission is performed. From the gear 316, the dispense gear 318 connected to the dispense auger 118 via the idler gear 317 is engaged.
In addition, the conveyance drive system 301 is connected to the rotation shaft of the rotation drive mechanism 230 of the cleaning unit 200 in addition to meshing the drive transmission gears 319 and 320 connected to the agitators 123 and 124 of the sub-toner replenishment unit 120 with the coaxial transmission gear 313. The drive transmission gear 321 is also engaged.
On the other hand, the development drive system 302 is provided with a drive transmission gear 331 coaxially with the photosensitive drum 31, for example, and the drive transmission gear 331 is engaged with a drive transmission gear 332 connected to the developing roll 103, and further this drive transmission gear 332. In this case, drive transmission gears 334 and 335 connected to the agitating and conveying augers 105 and 104 via the idler gear 333 are sequentially meshed.
The driving source of the development driving system 302 and the driving source of the conveyance driving system 301 are not limited to different modes, but the same driving source may be used as long as each can be driven independently.

As described above, according to the embodiment, since the transport drive system 301 and the development drive system 302 are separate systems, the toner transport member (as compared with the mode in which the development drive system 302 and the transport drive system 301 are interlocked) is used. The agitators 116 and 117, the dispense auger 118, the agitators 123 and 124), and the waste toner conveying member 220 need not always be driven during the developing operation, and accordingly, the wear deterioration of the toner conveying member and the waste toner conveying member 220 is suppressed, thereby reducing the process. The lifetime of the cartridge 30 can be improved.
In addition, since the toner conveying member or waste toner conveying member 220 having a large load fluctuation and the photosensitive drum 31 and the developing roll 103 that require rotational accuracy are driven separately, the toner conveying member, the waste toner conveying member 220, etc. The vibration caused by the load fluctuation does not affect the rotation of the photosensitive drum 31 and the developing roll 103, and image defects can be prevented in advance.
Furthermore, if the conveyance drive system 301 is provided with a connection element (such as a swinging gear) that can be connected to the drive elements of the toner supply units 110 and 120, the waste toner is separated from the toner supply operation. Only the transfer operation can be performed. Further, if a part of the driving element of the toner replenishing unit 110, for example, a connecting element that can be connected to the dispensing auger 118 is provided, the toner replenishing unit is not operated by the dispensing auger 118. It is also possible to perform the toner agitating and conveying operation only by the agitators 116, 117, 123, and 124 in the 110 and 120 to periodically loosen the replenishing toner.

Embodiment 2
14A to 14C show the toner supply port peripheral structure of the second embodiment of the developing device to which the present invention is applied.
In the figure, the basic configuration of the toner supply port peripheral structure is substantially the same as in the first embodiment, and the lower end of the toner supply port 115 is positioned below the surface position of the developer G stored in the developer storage chamber 102. And the toner transport direction at the portion facing the toner supply port 115 in the dispense chamber 113 and the developer transport direction at the portion facing the toner supply port 115 in the developer storage chamber 102. Although reversed, unlike the first embodiment, an extrusion paddle 150 along the axial direction is provided in a portion of the dispense auger 118 facing the toner supply port 115. Components similar to those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted here. The same applies to the following embodiments.
According to the present embodiment, in the vicinity of the toner supply port 115, a circulation flow (α direction, β direction) due to the toner T and the developer G is generated in substantially the same manner as in the first embodiment, and the toner supply in the dispense chamber 113 The toner T and the developer G are premixed in an area facing the mouth 115 (preliminary mixing area PM). At this time, in the premix area PM, the replenishment toner T and the developer G are pushed out from the toner supply port 115 to the developer storage chamber 102 while being agitated by the push paddle 150. Premixing improves.
Of course, a process cartridge and an image forming apparatus may be constructed by using the developing device according to the present embodiment. The same applies to the following embodiments.

Embodiment 3
FIGS. 15A to 15C show the toner supply port peripheral structure of the second embodiment of the developing device to which the present invention is applied.
In the figure, the basic configuration of the toner supply port peripheral structure is substantially the same as in the first embodiment, and the lower end of the toner supply port 115 is positioned below the surface position of the developer G stored in the developer storage chamber 102. However, unlike the first embodiment, the surface of the dispense auger 118 facing the toner supply port 115 is reversed. The auger blade pitch P2 of the portion thus formed is set wider than the other auger blade pitches P1. In this example, P1 is set to 4 to 8 mm, P2 is set to about 1.2 to 2 times, and is appropriately selected in consideration of the rotation speed based on the supplied toner amount. The auger blade pitch P3 of the admix auger 104 is appropriately selected in consideration of the toner conveyance amount by the dispense auger 118 and the like.
According to the present embodiment, in the vicinity of the toner supply port 115, a circulation flow (α direction, β direction) due to the toner T and the developer G is generated in substantially the same manner as in the first embodiment, and the toner supply to the dispense chamber 113 is performed. The toner T and the developer G are premixed in an area facing the mouth 115 (preliminary mixing area PM).
At this time, since the auger blade pitch P2 is set wider than the other auger blade pitches P1 in the premixed region PM, it is possible to take in a lot of developer G, and accordingly, the toner T and the developer G It is possible to improve the premixability with.

Embodiment 4
FIG. 16 is an explanatory diagram (corresponding to FIG. 6) showing a fourth embodiment of the developing device to which the present invention is applied.
In the drawing, the basic configuration of the developing device 33 is substantially the same as that of the first embodiment, but a structure different from that of the first embodiment is added to the edge of the toner supply port 115.
In the present embodiment, among the edges of the toner supply port 115, the toner T and the developer G are transported to the downstream edge of the toner transport direction and the developer transport direction at the portion facing the toner supply port 115. The hook-shaped return portions 161 and 162 facing each other are provided so as to protrude.
According to the present embodiment, one hook-shaped return portion 161 protrudes toward the developer accommodating chamber 102 and functions to receive a part of the developer G in the developer accommodating chamber 102 toward the toner supply port 115. The other hook-shaped return portion 162 protrudes toward the dispensing chamber 113 and serves to discharge the premixed toner and developer in the dispensing chamber 113 to the toner supply port 115 side.
For this reason, the receiving operation of the developer G (reverse flow operation of the developer) and the pre-mixed toner and developer discharging operation (replenishing operation of the toner after pre-mixing) are smoothly performed.
It should be noted that if the hook-shaped return portions 161 and 162 protrude too much, the original toner T carrying operation and the developer G carrying operation are hindered. Therefore, a range that does not cause trouble (for example, 0.2 mm to 2 mm). The degree may be selected as appropriate. That is, if the protrusion amount of the hook-shaped return portions 161 and 162 is appropriately selected, the return amount of the developer G is set as appropriate, and accordingly, the premixed amount of the toner T and the developer G is increased. Adjusted.

Embodiment 5
17 and 18 show a fifth embodiment of a developing device to which the present invention is applied.
In the drawing, the developing device 33 is formed by connecting a developing unit 100 and a toner replenishing unit 170 through a toner supply port 176, but unlike the first to fourth embodiments, the toner replenishing unit 170 includes a toner. The toner conveyance direction at the portion facing the supply port 176 is along a short direction different from the axial direction of the developing roller 103 in the developer accommodating chamber 102 of the developing unit 100.
That is, in the present embodiment, the developing unit 100 includes substantially the same components (the developing housing 101, the developer storage chamber 102, the developing roll 103, the agitating / conveying augers 104 and 105, the partition wall 106, the communication, and the like. Mouth 107, 108).
On the other hand, the toner replenishing unit 170 has a toner housing 171, a toner housing chamber 172 in which toner for replenishment is housed is provided in the toner housing 171, and an agitator 173 for stirring and transporting is disposed in the toner housing chamber 172. Further, one side in the longitudinal direction of the toner housing 171 and the developing housing 101 is connected to each other by a connecting duct 174, and a dispensing chamber 175 is secured in the connecting duct 174. A dispensing inlet opening 176 and a toner supply port 177 are opened in the vicinity of the communication port 108 on the side wall of the toner housing 171 and the developing housing 101, and a dispensing auger 178 for supplying a constant amount of toner is disposed in the dispensing chamber 175. Is.
In particular, in the present embodiment, the toner supply port 177 opens so that the lower end thereof is positioned below the surface position of the developer G stored in the developer storage chamber 102 and supplies the toner in the dispense chamber 175. The toner transport direction at the part facing the port 177 and the developer transport direction at the part facing the toner supply port 177 in the developer storage chamber 102 (from the supply auger 105 to the admix auger 104 via the communication port 108). Is equivalent to the direction of heading).

Therefore, according to the present embodiment, the toner supply unit 170 supplies the toner T in the toner storage chamber 172 to the developer storage chamber 102 of the development unit 100 via the dispense chamber 175.
At this time, since the end portion of the dispensing chamber 175 acts to keep the toner from clogging, the toner T and the developer G in the developer storage chamber 102 form a circulation flow as shown in the drawing near the toner supply port 177, and the dispensing is performed. A portion facing the toner supply port 177 in the chamber 175 functions as a premixing region PM, and the toner T and the developer G are premixed and then supplied to the developer storage chamber 102 through the toner supply port 177.

Embodiment 6
FIG. 19 shows a sixth embodiment of a developing device to which the present invention is applied.
In the present embodiment, the basic configuration of the developing device 33 is substantially the same as that of the fifth embodiment, but unlike the fifth embodiment, the longitudinal direction along the axial direction of the developing roller 103 in the developer storage chamber 102. In addition, the connecting duct 174 of the toner supply unit 170 is arranged to be inclined, and further, the agitator 173 in the toner storage chamber 172 is constituted by a stirring and conveying auger capable of supplying a fixed amount, and the connecting duct 174 and the developing housing 101 This connecting portion is a toner supply port 177, and the replenishment toner T is pushed out to the toner supply port 177 without disposing a dispense auger in the dispensing chamber 175 in the connecting duct 174.
Here, the toner supply port 177 opens so that its lower end is positioned below the surface position of the developer G stored in the developer storage chamber 102 and faces the toner supply port 177 in the dispense chamber 175. The toner transport direction at the part and the developer transport direction (corresponding to the developer transport direction by the admix auger 104 in this example) at the part facing the toner supply port 177 in the developer storage chamber 102 are reversed. It is what.
Components similar to those in the fifth embodiment are denoted by the same reference numerals as those in the fifth embodiment, and detailed description thereof is omitted here.

According to the present embodiment, the toner replenishment unit 170 replenishes the toner T in the toner storage chamber 172 to the developer storage chamber 102 of the development unit 100 via the dispense chamber 175.
At this time, since the end portion of the dispensing chamber 175 acts to keep the toner from clogging, the toner T and the developer G in the developer storage chamber 102 form a circulation flow as shown in the drawing near the toner supply port 177, and the dispensing is performed. A portion facing the toner supply port 177 in the chamber 175 functions as a premixing region PM, and the toner T and the developer G are premixed and then supplied to the developer storage chamber 102 through the toner supply port 177.
In the present embodiment, no dispense auger is provided in the dispense chamber 175, but a dispense auger may be provided if necessary.

(A) is an explanatory view showing a developing device according to the present invention, a process cartridge using the same, and an image forming apparatus, and (b) is a cross-sectional explanatory view taken along line BB in (a). 1 is an explanatory diagram showing Embodiment 1 of an image forming apparatus according to the present invention. It is explanatory drawing which shows the detail of the process cartridge used by this Embodiment. (A) is the arrow view which looked at the process cartridge used in this embodiment from one side, (b) is the arrow view which looked at the process cartridge used in this embodiment from the other side on the opposite side It is. It is explanatory drawing which shows the developing cartridge used in this Embodiment. It is VI-VI line partial fracture | rupture explanatory drawing in FIG. (A) is explanatory drawing which shows the toner supply port periphery structure of this Embodiment, (b) is a BB line disconnection figure in (a). FIG. 4 is an explanatory diagram illustrating an example of a communication structure between a main toner supply unit and a sub toner supply unit. It is principal part explanatory drawing of the cleaning apparatus used by this Embodiment. (A) (b) is explanatory drawing which shows the operation state of the urging | biasing spring at the time of forward / backward movement of a waste toner conveyance member. (A)-(c) is explanatory drawing which shows the operation state at the time of the waste toner conveyance member backward movement in the cleaning apparatus which concerns on Embodiment 1. FIG. (A)-(c) is explanatory drawing which shows the operation state at the time of the waste toner conveyance member advance movement. It is explanatory drawing which shows an example of the conveyance drive system used by this Embodiment, and a development drive system. (A) is explanatory drawing which shows the toner supply port periphery structure of Embodiment 2 of the developing device concerning this invention, (b) is a BB line disconnection figure in (a), (c) is C in (b). It is an arrow view seen from the direction. (A) is explanatory drawing which shows the toner supply port periphery structure of Embodiment 3 of the developing device which concerns on this invention, (b) is a BB disconnection figure in (a), (c) is C in (b). It is an arrow view seen from the direction. It is explanatory drawing which shows Embodiment 4 of the developing device which concerns on this invention. It is explanatory drawing which shows Embodiment 5 of the developing device which concerns on this invention. It is the XVIII-XVIII sectional view taken on the line in FIG. It is explanatory drawing which shows Embodiment 6 of the developing device which concerns on this invention. It is explanatory drawing which shows an example of the conventional developing device. (A) is explanatory drawing which shows the other example of the conventional developing apparatus, (b) is explanatory drawing which shows the developer supply mechanism, (c) is explanatory drawing which shows the developer collection | recovery mechanism.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Development unit, 2 ... Developer storage chamber, 2a ... Partition wall, 2b, 2c ... Communication port, 3 (3a, 3b) ... Developer stirring conveyance member, 4 ... Developer carrier, 5 ... Toner supply unit, 6... Toner replenishing chamber, 6 a. Mixing unit, 11 ... image carrier, 12 ... developing device, G ... developer, T ... toner

Claims (18)

A developer containing chamber containing a developer composed of toner and carrier, a developer stirring / conveying member disposed in the developer containing chamber, and the developer stirred and conveyed by the developer stirring / conveying member A developing unit provided with a developer carrying member capable of carrying and conveying;
It has a toner replenishing chamber for containing at least replenishing toner, a toner conveying member is disposed in the toner replenishing chamber, and communicates with the developer replenishing chamber of the developing unit via the toner supply port. A toner replenishment unit,
The toner supply port of the toner replenishing unit opens so that the lower end thereof is positioned below the surface position of the developer stored in the developer storage chamber,
A developing device that supplies replenishment toner to a developer storage chamber and reverses a part of the developer in the developer storage chamber in a direction opposite to the supply direction of the replenishment toner. The developing device according to claim 1,
A developing device characterized in that a shearing force is generated between the replenishing toner and the developer in the developer storage chamber. The developing device according to claim 1,
A developing device characterized in that the replenishment toner conveyance amount supplied to the developer storage chamber through the toner supply port is larger than the toner conveyance amount in the developer that flows backward. The developing device according to claim 1,
2. A developing device according to claim 1, wherein the distribution of the pressure by which the toner for replenishment in the toner replenishing unit is pushed out from the toner supply port includes a large portion and a small portion in comparison with the internal pressure by the developer in the developer storage chamber. The developing device according to claim 1,
The developing is characterized in that the toner transport direction in the portion of the toner supply chamber facing the toner supply port and the developer transport direction in the portion of the developer storage chamber facing the toner supply port are reversed. apparatus. The developing device according to claim 5, wherein
2. A developing device according to claim 1, wherein a toner conveying direction in a portion of the toner supply chamber facing the toner supply port is along a longitudinal direction of the developer containing chamber along the axial direction of the developer carrier. The developing device according to claim 5, wherein
2. A developing device according to claim 1, wherein a toner conveying direction in a portion of the toner replenishing chamber facing the toner supply port is along a short direction different from an axial direction of the developer carrying member in the developer containing chamber. The developing device according to claim 5, wherein
A developing device characterized in that a toner conveying direction in a portion of the toner replenishing chamber facing the toner supply port is inclined with respect to a longitudinal direction along the axial direction of the developer carrier in the developer containing chamber. The developing device according to claim 1,
2. A developing device according to claim 1, wherein the toner supply port is opened at a position distant from an end position of the developer storage chamber. The developing device according to claim 1,
Of the edge of the toner supply port, at the portion facing the toner supply port, the downstream edge of the toner transport direction and the developer transport direction is provided with a hook-shaped return portion facing the toner and developer transport directions. A developing device. The developing device according to claim 1,
2. A developing device according to claim 1, wherein the toner replenishing unit includes a toner conveying member facing the toner supply port, and a portion of the toner conveying member facing the toner supplying port is a premixing unit capable of premixing. The developing device according to claim 11, wherein
The toner replenishing chamber has a dispensing chamber formed at a portion facing the toner supply port and capable of quantitatively replenishing the replenishing toner, and a dispensing member for quantitative replenishment is disposed as a toner conveying member in the dispensing chamber. A developing device characterized in that a premixing section is provided in a part of the dispensing member. The developing device according to claim 12, wherein
A developing device, wherein the dispensing member is constituted by an auger, and a wing member for damming is provided as a premixing portion at a portion of the dispensing member facing the toner supply port. The developing device according to claim 11, wherein
A developing device comprising: a dispenser member configured by an auger; and a blade member extending along the axial direction as a premixing portion provided at a portion of the dispense member facing the toner supply port. The developing device according to claim 11, wherein
A developing device, wherein the dispensing member is constituted by an auger, and a blade pitch of a portion of the dispensing member facing the toner supply port is set wider than that of other portions to form a premixing unit. In the process cartridge that is detachably attached to the image forming apparatus main body,
16. A process cartridge comprising: an image carrier; and a developing device according to claim 1, which is arranged to face the image carrier and can visualize an electrostatic latent image on the image carrier.   An image forming apparatus comprising the process cartridge according to claim 16.   An image forming apparatus comprising: an image carrier; and the developing device according to claim 1 disposed opposite to the image carrier.

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